As is known urban and extraurban roads usually comprise a lot of dangerous zones, where are arranged rigid obstacles, such as pillars, bridge shoulders, parapets, lighting poles and the like, steel and concrete safety barriers and other types of obstacles.
In order to prevent an impact against these obstacles from causing serious damages to the occupants of an impacting vehicle, in front of the mentioned obstacles, in order to protect the latter, there are conventionally provided impact absorbing systems, specifically designed for absorbing the vehicle impact energy so as to decrease the speed of the vehicle, thereby reducing noxious effects of an impact on the vehicle occupants.
Several impact damping devices are known, which are usually based on the momentum transfer principle, and which conventionally comprise damping materials, such as water or sand, or which operate by exploiting a plastic deformation of an inner construction, for example made of mineral, metal or plastic materials, such as, for example, rigid foamed plastic materials.
While these systems have been found to provide quite good protecting characteristics, they have the disadvantage that they can not be reused, or can be only partially reused: then, a recovering thereof would require a long time and a high cost.
Thus, it would be advantageous to provide, for the road barrier field, impact absorbing systems of simple construction and susceptible to an easy and quick maintenance at a low cost.